**Background**
Central nervous system (CNS) disorders, including anxiety and depression, represent a significant global health burden. These conditions are often associated with imbalances in neurotransmitter systems, particularly the serotonergic system. The 5-HT 1A receptor, a G protein-coupled receptor, plays a critical role in regulating mood, anxiety, and cognitive functions. Modulating this receptor is a primary strategy for developing anxiolytic and antidepressant therapies. Understanding the underlying mechanisms of these receptors is essential for the discovery of more effective psychiatric medications. In this context, we will introduce a potent and selective 5-HT 1A receptor partial agonist – Tandospirone.
**Definition**
Tandospirone (SM-3997) is a selective 5-HT 1A receptor partial agonist with a Ki value of 27 nM. According to the Tandospirone description, this compound is utilized primarily in the research of CNS disorders and their associated molecular mechanisms.
**In Vitro and In Vivo Studies**
The Tandospirone biological activity is characterized by high selectivity for the 5-HT 1A receptor. Tandospirone In Vitro studies demonstrate that it is approximately two to three orders of magnitude less potent at 5-HT 2, 5-HT 1C, α1-adrenergic, α2-adrenergic, and dopamine D1 and D2 receptors, with Ki values ranging from 1300 to 41000 nM. Furthermore, it is essentially inactive at 5-HT 1B receptors, 5-HT uptake sites, beta-adrenergic, muscarinic cholinergic, and benzodiazepine receptors. Mechanistically, it activates postsynaptic 5-HT 1A receptors coupled with G-protein (Gi/o), which inhibits protein kinase A (PKA)-mediated protein phosphorylation and subsequent neuronal activity.
Tandospirone In Vivo research has focused on behavioral models of stress. In seven-week-old male Sprague-Dawley rats (260-300 g) using a conditioned fear stress-induced freezing behavior model, Tandospirone (10-80 mg/kg; i.p.) inhibited freezing behavior in a dose-dependent manner. Additionally, the anxiolytic effect was found to be dependent on the plasma concentration at 0.5 hours post-administration, though this effect was not observed at 4 hours. For researchers seeking specific Tandospirone technical information regarding its application in these models, these results highlight its potential as a tool for studying fear and anxiety. In conclusion, Tandospirone is a potent and selective 5-HT 1A receptor partial agonist with significant anxiolytic and antidepressant activities.
Keywords
Tandospirone, 87760-53-0, SM-3997, SM3997, SM 3997, 5-HT Receptor, Serotonin Receptor, 5-hydroxytryptamine Receptor, 5-hydroxytryptamine, anxiety, disorder, depression, Parkinson’s disease, schizophrenia, central
References
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[2] Xuefei Huang, et al. Role of tandospirone, a 5-HT1A receptor partial agonist, in the treatment of central nervous system disorders and the underlying mechanisms. Oncotarget. 2017 Nov 24; 8(60): 102705–102720.
[3] Kyoko Nishitsuji, et al. The pharmacokinetics and pharmacodynamics of tandospirone in rats exposed to conditioned fear stress. Eur Neuropsychopharmacol. 2006 Jul;16(5):376-82.